1. Field of the invention
The present invention is generally concerned with hinges and is more particularly but not necessarily exclusively directed to those designed to be fitted to eyeglass frames.
2. Description of the prior art
Taken as a whole, a hinge comprises two parts articulated to each other by a pin.
In an eyeglass frame a hinge of this kind is usually operative between the front assembly and each of the side support temples, for the purpose of folding the latter.
In practice, for each of these lateral support temples one of the component parts of the hinge employed is part of the front assembly, where it forms a yoke at the end of a tenon, for example, while the other forms part of the lateral support temple itself, where it forms a knuckle, for example, which is inserted between the two branches of the previously mentioned yoke, although the converse arrangement is equally possible.
One problem in providing hinges of this type resides in the fact that it is necessary to secure in some appropriate way the pin which forms the articulation axis.
To this end, in eyeglass frames the pin is usually a screw which has an appropriately threaded end portion which screws into a threaded opening in one of the branches of the yoke concerned and which has a head in axial bearing engagement with the other branch.
However, although various palliative measures of all kinds are routinely deployed to oppose this, it is not at all rare for a screw of this kind to become unscrewed in service and/or for wear of the parts concerned to occur, which in either case is detrimental to the retention of the corresponding lateral support temple.
A general object of the present invention is an arrangement which provides a simple and effective solution to the problem of retaining the pin of a hinge in the axial direction.